javaScript小知识

<script language=javascript>
var t=3.1415;
alert( "int("+t+") = "+int(t) );
alert( "parseInt("+t+") = "+parseInt(t) );
alert( "Math.floor("+t+") = " +Math.floor(t) );
alert( "Math.round("+t+") = "+Math.round(t) );
alert( "Math.ceil("+t+") = " +Math.ceil(t) );
function int(num){return num-num%1}
</script>

 

按钮可用状态倒计时...(JavaScript)

今天在一个网站注册的时候, 看到了在服务条款和声明的时候, 我同意这个按钮要等几秒钟才可用, 虽然以前也看到过, 但这几天实在是闲着无聊, 所以, 嘿, 咱也来一个吧.

<form name="frm">
<input type="submit" name="btnSubmit" value="我同意" />
</form>

<script language="javascript">
<!--
var sec = 9;
var wait = sec * 1000;
document.frm.btnSubmit.value = "我同意[" + sec + "]";
document.frm.btnSubmit.disabled = true;

for(var i = 0; i <= sec; i++) {
window.setTimeout("TimeUpdate(" + i + ")", i * 1000);
}

window.setTimeout("TimeOk()", wait);

function TimeUpdate(num) {
if(num != sec) {
   var pntNum = (wait / 1000) - num;
   document.frm.btnSubmit.value = "我同意[" + pntNum + "]";
}
}

function TimeOk() {
document.frm.btnSubmit.value = "我同意";
document.frm.btnSubmit.disabled = false;
}
//-->
</script>

第一种：精确到秒的javascript倒计时代码

HTML代码:

< form name=" form1">
< div align=" center" align=" middle">
< center>离2010年还有:< br>
< input type=" textarea" name=" left" size=" 35" style=" text-align: center">
< /center>
< /div>
< /form>
< script LANGUAGE=" javascript">
startclock()
var timerID = null;
var timerRunning = false;
function showtime() {
Today = new Date();
var NowHour = Today.getHours();
var NowMinute = Today.getMinutes();
var NowMonth = Today.getMonth();
var NowDate = Today.getDate();
var NowYear = Today.getYear();
var NowSecond = Today.getSeconds();
if (NowYear <2000)
NowYear=1900+NowYear;
Today = null;
Hourleft = 23 - NowHour
Minuteleft = 59 - NowMinute
Secondleft = 59 - NowSecond
Yearleft = 2009 - NowYear
Monthleft = 12 - NowMonth - 1
Dateleft = 31 - NowDate
if (Secondleft<0)
{
Secondleft=60+Secondleft;
Minuteleft=Minuteleft-1;
}
if (Minuteleft<0)
{
Minuteleft=60+Minuteleft;
Hourleft=Hourleft-1;
}
if (Hourleft<0)
{
Hourleft=24+Hourleft;
Dateleft=Dateleft-1;
}
if (Dateleft<0)
{
Dateleft=31+Dateleft;
Monthleft=Monthleft-1;
}
if (Monthleft<0)
{
Monthleft=12+Monthleft;
Yearleft=Yearleft-1;
}
Temp=Yearleft+'年, '+Monthleft+'月, '+Dateleft+'天, '+Hourleft+'小时, '+Minuteleft+'分, '+Secondleft+'秒'
document.form1.left.value=Temp;
timerID = setTimeout("showtime()",1000);
timerRunning = true;
}
var timerID = null;
var timerRunning = false;
function stopclock () {
if(timerRunning)
clearTimeout(timerID);
timerRunning = false;
}
function startclock () {
stopclock();
showtime();
}
// -->
< /script>

第二种：某某运动会

HTML代码:

< !--倒计时Javascript begin-->
< script language=" JavaScript">
<!--
function DigitalTime1()
{
var deadline= new Date("08/13/2007") //开幕倒计时
var symbol="8月13日"
var now = new Date()
var diff = -480 - now.getTimezoneOffset() //是北京时间和当地时间的时间差
var leave = (deadline.getTime() - now.getTime()) + diff*60000
var day = Math.floor(leave / (1000 * 60 * 60 * 24))
var hour = Math.floor(leave / (1000*3600)) - (day * 24)
var minute = Math.floor(leave / (1000*60)) - (day * 24 *60) - (hour * 60)
var second = Math.floor(leave / (1000)) - (day * 24 *60*60) - (hour * 60 * 60) - (minute*60)

var deadline_2= new Date("08/13/2004") //开幕后计时
var symbol_2="8月13日"
var now_2 = new Date()
var diff_2 = -480 - now.getTimezoneOffset() //是北京时间和当地时间的时间差
var leave_2 = (now_2.getTime() - deadline_2.getTime()) + diff_2*60000
var day_2 = Math.floor(leave_2 / (1000 * 60 * 60 * 24))
var hour_2 = Math.floor(leave_2 / (1000*3600)) - (day_2 * 24)
var minute_2 = Math.floor(leave_2 / (1000*60)) - (day_2 * 24 *60) - (hour_2 * 60)
var second_2 = Math.floor(leave_2 / (1000)) - (day_2 * 24 *60*60) - (hour_2 * 60 * 60) - (minute_2*60)

day=day+1;
day_2=day_2+1;

if (day>0) //还未开幕
{
//LiveClock1.innerHTML = "现在"+symbol+"天"
LiveClock1.innerHTML = "< font class=fon1>距离"+symbol+"开幕还有< font class=fon2>"+day+"< /font>天< /font>"
setTimeout("DigitalTime1()",1000)
}

if (day<0) //已经开幕
{
//LiveClock1.innerHTML = "现在离"+symbol+"还有"+day+"天"+hour+"小时"+minute+"分"+second +"秒"
LiveClock1.innerHTML = "< font class=fon1>"+symbol+"开幕已有< font class=fon2>"+day_2+"< /font>天< /font>"
setTimeout("DigitalTime1()",1000)

}

if (day==0) //正在开幕
{
//LiveClock1.innerHTML = "现在"+symbol+"天"
LiveClock1.innerHTML = "< font class=fon1>某某运动会今天开幕< /font>"
setTimeout("DigitalTime1()",1000)
}



if (day<0 & day_2>19) //某某运动会结束
{
//LiveClock1.innerHTML = "现在离"+symbol+"还有"+day+"天"+hour+"小时"+minute+"分"+second +"秒"
LiveClock1.innerHTML = "< font class=fon1>某某运动会已全部结束< /font>"
setTimeout("DigitalTime1()",1000)

}

}
// -->
< /script>
< !--倒计时Javascript end-->
< body onload=DigitalTime1()>
< div id= LiveClock1>< /div>

< /body>

第三种：小时倒计时

HTML代码:

< SCRIPT LANGUAGE=" JavaScript">
<!--
var maxtime = 60*60 //一个小时，按秒计算，自己调整!
function CountDown(){
if(maxtime>=0){
minutes = Math.floor(maxtime/60);
seconds = Math.floor(maxtime%60);
msg = "距离结束还有"+minutes+"分"+seconds+"秒";
document.all["timer"].innerHTML=msg;
if(maxtime == 5*60) alert('注意，还有5分钟!');
--maxtime;
}
else{
clearInterval(timer);
alert("时间到，结束!");
}
}
timer = setInterval("CountDown()",1000);
//-->
< /SCRIPT>
< div id=" timer" style=" color:red">< /div>

第四种：最简倒计时

HTML代码:

< Script Language=" JavaScript">
<!-- Begin
　　var timedate= new Date("January 14,2006");
　　var times="研究生考试";
　　var now = new Date();
　　var date = timedate.getTime() - now.getTime();
　　var time = Math.floor(date / (1000 * 60 * 60 * 24));
　　if (time >= 0) ;
document.write("< li>< font color=#DEDBDE>现在离2006年"+times+"还有: < font color=#ffffff>< b>"+time +"< /b>< /font> 天< /font>< /li>");
// End -->
< /Script>

第四种：最简倒计时二

HTML代码:

< script language=" JavaScript" type=" text/javascript">
function djs(){
var urodz= new Date("11/12/2008");　
var now = new Date();
var num
var ile = urodz.getTime() - now.getTime();　　
var dni = Math.floor(ile / (1000 * 60 * 60 * 24));　　
if (dni >1)　　
num=dni+1
else if (dni == 1)　num=2　
else if (dni == 0)　num=1
else num=0　
document.write(num)　　
}
< /script>

距某某开幕式还有 [< script language=" JavaScript" type=" text/javascript">djs()< /script>] 天

第五个：Javascript倒计时器 - 采用系统时间自校验

这次利用系统时间自校验倒计时, 无需手工调校使得倒计时更为精确, 代码及详细注释如下:

<span id="clock">00:01:11:00</span>
<input id="startB" type="button" value="start countdown!" onclick="run()">
<input id="endB" type="button" value="stop countdown!" onclick="stop()">
<br>
<input id="diff" type="text">
<input id="next" type="text">
<script language="Javascript">
/* This notice must be untouched at all times.

countdown.js    v. 1.0
The latest version is available at
http://blog.csdn.net/yjgx007

Copyright (c) 2004 Xinyi.Chen. All rights reserved.
Created 7/30/2004 by Xinyi.Chen.
Web: http://blog.csdn.net/yjgx007
E-Mail: [email protected]
Last modified: 7/30/2004

This program is free software;
you can redistribute it and/or modify it under the terms of the
GNU General Public License as published by the Free Software Foundation;

See the GNU General Public License
at http://www.gnu.org/copyleft/gpl.html for more details.
*/
var normalelapse = 100;
var nextelapse = normalelapse;
var counter;
var startTime;
var start = clock.innerText;
var finish = "00:00:00:00";
var timer = null;

// 开始运行
function run() {
startB.disabled = true;
endB.disabled = false;
counter = 0;
// 初始化开始时间
startTime = new Date().valueOf();

// nextelapse是定时时间, 初始时为100毫秒
// 注意setInterval函数: 时间逝去nextelapse(毫秒)后, onTimer才开始执行
timer = window.setInterval("onTimer()", nextelapse);
}

// 停止运行
function stop() {
startB.disabled = false;
endB.disabled = true;
window.clearTimeout(timer);
}

window.onload = function() {
endB.disabled = true;
}

// 倒计时函数
function onTimer()
{

if (start == finish)
{
window.clearInterval(timer);
alert("time is up!");
return;
}

var hms = new String(start).split(":");
var ms = new Number(hms[3]);
var s = new Number(hms[2]);
var m = new Number(hms[1]);
var h = new Number(hms[0]);

ms -= 10;
if (ms < 0)
{
ms = 90;
s -= 1;
if (s < 0)
{
    s = 59;
    m -= 1;
}

if (m < 0)
{
    m = 59;
    h -= 1;
}
}

var ms = ms < 10 ? ("0" + ms) : ms;
var ss = s < 10 ? ("0" + s) : s;
var sm = m < 10 ? ("0" + m) : m;
var sh = h < 10 ? ("0" + h) : h;

start = sh + ":" + sm + ":" + ss + ":" + ms;
clock.innerText = start;

// 清除上一次的定时器
window.clearInterval(timer);

// 自校验系统时间得到时间差, 并由此得到下次所启动的新定时器的时间nextelapse
counter++;
var counterSecs = counter * 100;
var elapseSecs = new Date().valueOf() - startTime;
var diffSecs = counterSecs - elapseSecs;
nextelapse = normalelapse + diffSecs;
diff.value = counterSecs + "-" + elapseSecs + "=" + diffSecs;
next.value = "nextelapse = " + nextelapse;
if (nextelapse < 0) nextelapse = 0;

// 启动新的定时器
timer = window.setInterval("onTimer()", nextelapse);
}
</script>

 

----------------------------------------------------

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>JavaScript动态显示当前时间和倒计时的设计</title>
<script language="javascript" type="text/javascript">
<!--
//获得当前时间,刻度为一千分一秒
var initializationTime=(new Date()).getTime();
function showLeftTime()
{
var now=new Date();
var year=now.getYear();
var month=now.getMonth();
var day=now.getDate();
var hours=now.getHours();
var minutes=now.getMinutes();
var seconds=now.getSeconds();
document.all.show.innerHTML="当前时间:"+year+"年"+month+"月"+day+"日"+hours+"小时"+minutes+"分"+seconds+"秒";
//设定结束时间
//1秒=1000毫秒
endTime=initializationTime+60000;
//设定并显示剩余时间

var leftTime=endTime-(new Date()).getTime();
if(leftTime>0)
{
document.all.showLeft.innerHTML=leftTime+"微秒后停止!";
}
else
{
clearTimeout(timeID);
document.all.showLeft.innerHTML="TimeOut!";
return false;
}
//一秒刷新一次显示时间
var timeID=setTimeout(showLeftTime,1000);
}
//-->
</script>
</head>
<body onload="showLeftTime()">
<label id="show">这里显示开始时间</label><br>
<label id="showLeft">这里显示剩余时间</label>
</body>
</html>

 

------------------------------------------------

JavaScript页面多个倒计时

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gbk" />
<title>多个倒计时</title>
<meta name="author" content="Aken [email protected]" />

<script language=javascript>
var array1 = new Array();
var array2 = new Array();
var timerId = new Array();
array1.push(60);
array2.push(0);
array1.push(70);
array2.push(1);
array1.push(50);
array2.push(2);
array1.push(40);
array2.push(3);
array1.push(55);
array2.push(4);
function test(){
for(var i=0;i<array1.length;i++){
timer=setInterval("ee('"+array2[i]+"','"+i+"');",1000);
timerId.push(timer);
}    

}

function ee(id,i){
//alert(t+"/"+id);
array1[i]=array1[i]-1;
document.getElementById('input'+id).innerHTML=array1[i];
}
function stop(id){
//array1[id]=100;
clearInterval(timerId[id]);
}

</script>
</head>
<body>

<input type = "button" value = "start" onclick = "test();"/><br/>
<span id="input0">time</span>
<input type = "button" value = "stop" onclick = "stop(0);"/><br/>
<span id="input1">time</span>
<input type = "button" value = "stop" onclick = "stop(1);"/><br/>
<span id="input2">time</span>
<input type = "button" value = "stop" onclick = "stop(2);"/><br/>
<span id="input3">time</span>
<input type = "button" value = "stop" onclick = "stop(3);"/><br/>
<span id="input4">time</span>
<input type = "button" value = "stop" onclick = "stop(4);"/><br/>
</body>